Perhaps you should try some spelling variations:
su sach » so sach, vu sach
hang di » hang doi, hang vi, hang dien
hanh di » hanh vi, hanh de, danh di
tuc van » thuc van, truc van, tuc va
dau tuc » dau tu, dao tuc, cau truc
ty hang » ly hang, ty xang, thi hang
ty nang » ky nang, ty xang, ly nang
cuu tre » cua tre, cau tren, cau treo
va dau » va dao

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((ty nang) OR (ty hang)) xa hoi. lieu va dau tuc van ((hanh di) or (hang di)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ty nang) OR (ty hang)) xa hoi. lieu va dau tuc van ((hanh di) OR (hang di)) cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ty nang) OR (ty hang)) xa hoi. lieu va dau tuc van ((hanh di) or (hang di)) cuu tre*".